Skip to content
Heist/ feed
Back to feed
UnratedFix available

batman-adv: tp_meter: restrict number of unacked list entries

Type: advisorySources: OSV

In the Linux kernel, the following vulnerability has been resolved: batman-adv: tp_meter: restrict number of unacked list entries When the unacked_list is unbound, an attacker could send messages with small lengths and appropriated seqno + gaps to force the receiver to allocate more and more unacked_list entries. And the end either causing an out-of-memory situation or increase the management overhead for the (large) list that significant portions of CPU cycles are wasted in searching through the list. When limiting the list to a specific number, it is important to still correctly add a new entry to the list. But if the list became larger than the limit, the last entry of the list (with the highest seqno) must be dropped to still allow the earlier seqnos to finish and therefore to continue the process. Otherwise, the process might get stuck with too high seqnos which are not handled by batadv_tp_ack_unordered().

Products
Kernel
Affected versions
Not specified
Fixed versions
5.10.260, 5.15.211, 6.1.177, 6.12.95, 6.18.38, 6.6.144, 7.1.3
CVEs
CVE-2026-63834
Confirmed fixed CVEs
Not specified
Updated in this feed
4 Nov 2026, 02:35 UTC · Revision 1

Source evidence

batman-adv: tp_meter: restrict number of unacked list entries

core-osv · Original source

Published 19 Jul 2026, 12:02 UTC

In the Linux kernel, the following vulnerability has been resolved: batman-adv: tp_meter: restrict number of unacked list entries When the unacked_list is unbound, an attacker could send messages with small lengths and appropriated seqno + gaps to force the receiver to allocate more and more unacked_list entries. And the end either causing an out-of-memory situation or increase the management overhead for the (large) list that significant portions of CPU cycles are wasted in searching through the list. When limiting the list to a specific number, it is important to still correctly add a new entry to the list. But if the list became larger than the limit, the last entry of the list (with the highest seqno) must be dropped to still allow the earlier seqnos to finish and therefore to continue the process. Otherwise, the process might get stuck with too high seqnos which are not handled by batadv_tp_ack_unordered().

osv:CVE-2026-63834

Kernel

Fixed versions: 5.10.260, 5.15.211, 6.1.177, 6.6.144, 6.12.95, 6.18.38, 7.1.3

Complete source record
{
  "id": "37976d0c6223b8807923285e7adfe55925dd00d9dda29b92fa27dbe2dd555442",
  "url": "https://osv.dev/vulnerability/CVE-2026-63834",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "batman-adv: tp_meter: restrict number of unacked list entries",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: batman-adv: tp_meter: restrict number of unacked list entries When the unacked_list is unbound, an attacker could send messages with small lengths and appropriated seqno + gaps to force the receiver to allocate more and more unacked_list entries. And the end either causing an out-of-memory situation or increase the management overhead for the (large) list that significant portions of CPU cycles are wasted in searching through the list. When limiting the list to a specific number, it is important to still correctly add a new entry to the list. But if the list became larger than the limit, the last entry of the list (with the highest seqno) must be dropped to still allow the earlier seqnos to finish and therefore to continue the process. Otherwise, the process might get stuck with too high seqnos which are not handled by batadv_tp_ack_unordered().",
    "evidence": "osv:CVE-2026-63834",
    "products": [
      {
        "name": {
          "value": "Kernel",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "5.10.260",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "5.15.211",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.1.177",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.6.144",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.12.95",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.18.38",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "7.1.3",
            "evidence": "/affected/1/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "unknown",
    "structured": {
      "id": "CVE-2026-63834",
      "aliases": [
        "CVE-2026-63834"
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "type": "GIT",
              "events": [
                {
                  "introduced": "33a3bb4a3345bb511f9c69c913da95d4693e2a4e"
                },
                {
                  "fixed": "31a88792bfba142be3c9521538c1db805677381f"
                },
                {
                  "fixed": "1111a3381bca2d1f084a07686bc783af5ab23df7"
                },
                {
                  "fixed": "1c616b0be4bd8399d485e25e91859373b95d6013"
                },
                {
                  "fixed": "f8c499fd275e59203b77fca76ae6ef2d096c2133"
                },
                {
                  "fixed": "c6231d628d06d841bc1617b2f7034f5f39876b16"
                },
                {
                  "fixed": "2233787658db859f0a9b83cb397cf783bb8be865"
                },
                {
                  "fixed": "1fb8762600a393d1caccd63be5d07e1756982d68"
                },
                {
                  "fixed": "e7c775110e1858e5a7471a23a9c9658c0af9df89"
                }
              ]
            }
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-63834.json"
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "4.8.0"
                },
                {
                  "fixed": "5.10.260"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "5.11.0"
                },
                {
                  "fixed": "5.15.211"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "5.16.0"
                },
                {
                  "fixed": "6.1.177"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.2.0"
                },
                {
                  "fixed": "6.6.144"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.7.0"
                },
                {
                  "fixed": "6.12.95"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.13.0"
                },
                {
                  "fixed": "6.18.38"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.19.0"
                },
                {
                  "fixed": "7.1.3"
                }
              ]
            }
          ],
          "package": {
            "name": "Kernel",
            "ecosystem": "Linux"
          },
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-63834.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:32.637729812Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/1111a3381bca2d1f084a07686bc783af5ab23df7",
        "https://git.kernel.org/stable/c/1c616b0be4bd8399d485e25e91859373b95d6013",
        "https://git.kernel.org/stable/c/1fb8762600a393d1caccd63be5d07e1756982d68",
        "https://git.kernel.org/stable/c/2233787658db859f0a9b83cb397cf783bb8be865",
        "https://git.kernel.org/stable/c/31a88792bfba142be3c9521538c1db805677381f",
        "https://git.kernel.org/stable/c/c6231d628d06d841bc1617b2f7034f5f39876b16",
        "https://git.kernel.org/stable/c/e7c775110e1858e5a7471a23a9c9658c0af9df89",
        "https://git.kernel.org/stable/c/f8c499fd275e59203b77fca76ae6ef2d096c2133",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/63xxx/CVE-2026-63834.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-63834",
        "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
      ],
      "provider_metadata": {
        "cna_assigner": "Linux",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/63xxx/CVE-2026-63834.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-63834",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": null
  },
  "source_id": "core-osv",
  "document_id": 499738,
  "published_at": "2026-07-19T12:02:26.045+00:00"
}